What are normal rpms for a scoot at WOT?  By  B. A. M. F. (Read 13,288 times)

unlimeted cdi helps mostly when ur transmision is all tweaked thats the most power gain ive seem the cdi help

I have a 150 and if i am doing alot of cruising I put my 13g sliders in,,it will tach about 5800 WOT from a stop,,then go up to 7500 after 55 mph,,if I want to rip roar around town I put in the 12g rollers and she will run about 6900 right out of the box,,pull hard to 50 then at 55 rev around 8k,,too high for my liking,,so i leave heavy sliders in and just cruise around at between 5 and 6k pull any hill around here at 35 mph,,I want my motor to last.

9700 rpms seems dangerous.

[replyingto=jeepsteve92xj]jeepsteve92xj[/replyingto]Was that on a GY6 150 bro?

Wow!

And Im worried about 7k...lol

Yes, a stock gy6 150 Znen motor - which as it turns out has a 12 pole stator - from the factory. 1" header and shorty muffler, 110 jet. Stock air box.
It had heavy rollers - 17gram or 18 gram... has 10gram sliders in it now, should have 12 by the end of tomorrow

BAMF first thing I would do is remove your roller weights and weigh them with a digital scale to have a starting base . My 4T " secret 63 " came with 8 grams but Im 200lbs and it is hilly here I went with 5 grams and wow take off and uphill were improved , top end was the same but the RPMs were higher . Unsure of the numbers since no tach . I think the redline is 8000 RPMs on a stock 139qmb but 7k is as far as you would want to go as above that will wear out parts faster and have more risk of blowing it up etc . Here is a link to a CVT tuning kit with several weights that you can try out a few combos and even mix up like 3 5g and 3 6 to equal 5.5g . Once you find a weight that works best get 1 gram heavier in sliders instead of rollers . I use Dr Pulley sliders in my scoots and I love em . Sliders are quieter , last waaaay longer , and perform better than rollers .

On my 2T which was stock other than NGK iridium and went from 68 main jet to a 75 it would top out at 8k . I could rev it up higher on the center stand than 8k . Going downhill it could hit 9k but would fizzle and stall . I bought a blue finned racing CDI from PFS that my dealer had on hand . Yes it has advanced timing and no rev limit . Takeoff and midrange was a hair better but still topped at 8k . My dealer suggested I tried lighter weights . I removed then and noted that I did not have a restricted washer in the variator like some and that I had 6g . Tried 4g and it was too light as it sounded like it over revved on low end , lost 5 MPH on top end and still maxed at 8k . I mixed then up to equal 5g and liked it . I later bought a Uni vent cover not the big red air filter like I should have and also replaced the 75MJ with a . Wow it was a lil louder with the sound of the air being sucked in and midrange way better . I am lucky that my scoot came with a 19mm carb as many are 17.5 or smaller and a decent pipe with an expansion chamber . The expansion chamber is necessary for a 2T to develop power in the top end . Many come with only tubing and a muffler with no expansion chamber . The posts you read with people hitting high RPMs is because most have replaced the airbox with a Uni or K&N style air filter , and ether replaced the stock exhaust with a less or unrestricted one or drilled holes in the muffler . Both mods will require a larger main jet in the carb and adjusting the air/fuel screw . I bough the proper Uni but my dealer nor any of the several scooter and motorcycle shops had jets that would fit in my carb . So being impatient I decided to go around the block anyways . Will it had a slight bog but not like it was stalling and ( censored ) it soft seized on me .

I tried to start it up after it cooled no luck . Pulled the engine apart and the rings were fried and the cylinder scarred . I put on a 47mm BBK 70cc , a racing pipe and I had a few larger jets to mess with . I first tried too large of jet and the small Uni it ran like crap . Put on the big red Uni was better but still flooding . I went down to a smaller MJ and tada it was beyond day and night better . With the Uni , pipe , CDI and upjetting I can now hit 10,500 RPMs . With the 5g rollers I could do 50 MPH ( according to the speedo ) let up then hit WOT and with a lil pull I would pop a wheelie for a few feet

Here is a link to the CVT weight tuning kit enviromoto.ecrater.com/p/14177743/prima-roller-weight-kit-16-x-13

Here is a derestricting set of tips www.scootnfast.com/scooter/Tuning_mods/De-Restricting.htm

This is a tuning tip page www.provoscooter.com/tuning

Listen to MillSC as his 50mm BBK is a beast after he had big valve head ported , after market exhaust and a whopping 24mm carb

I have an implement / lawnmower combination hour meter + tach.
just like this -
www.ebay.com/itm/Digital-Tach-Hour-Meter-Tachometer-Gauge-Spark-Plugs-Gas-Engine-Motocycle-ATV-/161039430085?pt=LH_DefaultDomain_0&hash=item257eb2b1c5

Be sure to shop around, the prices on ebay alone range from $10-ish up over $50 for the same model/style.